Liquid crystal composition and liquid crystal display device

ABSTRACT

Provided are a liquid crystal composition satisfying at least one of characteristics such as high maximum temperature, low minimum temperature, small viscosity, suitable optical anisotropy, large negative dielectric anisotropy, large specific resistance, high stability to ultraviolet light and high stability to heat, or the liquid crystal composition having a suitable balance regarding at least two of the characteristics; and an AM device having characteristics such as a short response time, a large voltage holding ratio, low threshold voltage, a large contrast ratio and a long service life. The liquid crystal composition has negative dielectric anisotropy and contains a specific compound having large negative dielectric anisotropy as a first component, a specific compound having low minimum temperature as a second component, and a specific compound having small viscosity as a third component, and the composition may contain a specific compound having high maximum temperature or small viscosity as a fourth component, a specific compound having negative dielectric anisotropy as a fifth component, or a specific compound having a polymerizable group as an additive component.

TECHNICAL FIELD

The invention relates to a liquid crystal composition, a liquid crystaldisplay device including the composition, and so forth. In particular,the invention relates to a liquid crystal composition having negativedielectric anisotropy, and a liquid crystal display device that includesthe composition and has a mode such as an IPS mode, a VA mode, an FFSmode and an FPA mode. The invention also relates to a liquid crystaldisplay device having a polymer sustained alignment mode.

BACKGROUND ART

In a liquid crystal display device, a classification based on anoperating mode for liquid crystal molecules includes a phase change (PC)mode, a twisted nematic (TN) mode, a super twisted nematic (STN) mode,an electrically controlled birefringence (ECB) mode, an opticallycompensated bend (OCB) mode, an in-plane switching (IPS) mode, avertical alignment (VA) mode, a fringe field switching (FFS) mode and afield-induced photo-reactive alignment (FPA) mode. A classificationbased on a driving mode in the device includes a passive matrix (PM) andan active matrix (AM). The PM is classified into static, multiplex andso forth, and the AM is classified into a thin film transistor (TFT), ametal insulator metal (MIM) and so forth. The TFT is further classifiedinto amorphous silicon and polycrystal silicon. The latter is classifiedinto a high temperature type and a low temperature type based on aproduction process. A classification based on a light source includes areflective type utilizing natural light, a transmissive type utilizingbacklight and a transflective type utilizing both the natural light andthe backlight.

The liquid crystal display device includes a liquid crystal compositionhaving a nematic phase. The composition has suitable characteristics. AnAM device having good characteristics can be obtained by improvingcharacteristics of the composition. Table 1 below summarizes arelationship in two characteristics. The characteristics of thecomposition will be further described based on a commercially availableAM device. A temperature range of the nematic phase relates to atemperature range in which the device can be used. A preferred maximumtemperature of the nematic phase is about 70° C. or higher, and apreferred minimum temperature of the nematic phase is about −10° C. orlower. Viscosity of the composition relates to a response time in thedevice. A short response time is preferred for displaying moving imageson the device. A shorter response time even by one millisecond isdesirable. Accordingly, a small viscosity in the composition ispreferred. A small viscosity at low temperature is further preferred.

TABLE 1 Characteristics of Composition and AM Device No. Characteristicsof Composition Characteristics of AM Device 1 Wide temperature range ofa Wide usable temperature range nematic phase 2 Small viscosity Shortresponse time 3 Suitable optical anisotropy Large contrast ratio 4 Largepositive or negative Low threshold voltage and dielectric anisotropysmall electric power consumption Large contrast ratio 5 Large specificresistance Large voltage holding ratio and large contrast ratio 6 Highstability to ultraviolet Long service life light and heat

Optical anisotropy of the composition relates to a contrast ratio in thedevice. According to a mode of the device, large optical anisotropy orsmall optical anisotropy, more specifically, suitable optical anisotropyis required. A product (Δn×d) of the optical anisotropy (Δn) of thecomposition and a cell gap (d) in the device is designed so as tomaximize the contrast ratio. A suitable value of the product depends ona type of the operating mode. In a device having the VA mode, the valueis in the range of about 0.30 micrometer to about 0.40 micrometer, andin a device having the IPS mode or the FFS mode, the value is in therange of about 0.20 micrometer to about 0.30 micrometer. In the abovecase, a composition having large optical anisotropy is preferred for adevice having a small cell gap. Large dielectric anisotropy in thecomposition contributes to low threshold voltage, small electric powerconsumption and a large contrast ratio in the device. Accordingly, thelarge dielectric anisotropy is preferred. Large specific resistance inthe composition contributes to a large voltage holding ratio and thelarge contrast ratio in the device. Accordingly, a composition havingthe large specific resistance at room temperature and also at atemperature close to the maximum temperature of the nematic phase in aninitial stage is preferred. The composition having the large specificresistance at room temperature and also at a temperature close to themaximum temperature of the nematic phase even after the device has beenused for a long period of time is preferred. Stability of thecomposition to ultraviolet light and heat relates to a service life ofthe device. In the case where the stability is high, the device has along service life. Such characteristics are preferred for an AM deviceuse in a liquid crystal projector, a liquid crystal television and soforth.

In a liquid crystal display device having a polymer sustained alignment(PSA) mode, a liquid crystal composition containing a polymer is used.First, a composition to which a small amount of a polymerizable compoundis added is injected into the device. Next, the composition isirradiated with ultraviolet light while voltage is applied betweensubstrates of the device. The polymerizable compound is polymerized toform a network structure of the polymer in the composition. In thecomposition, alignment of liquid crystal molecules can be controlled bythe polymer, and therefore the response time in the device is shortenedand also image persistence is improved. Such an effect of the polymercan be expected for a device having the mode such as the TN mode, theECB mode, the OCB mode, the IPS mode, the VA mode, the FFS mode and theFPA mode.

A composition having positive dielectric anisotropy is used in an AMdevice having the TN mode. A composition having negative dielectricanisotropy is used in an AM device having the VA mode. In an AM devicehaving the IPS mode or the FFS mode, a composition having positive ornegative dielectric anisotropy is used. In an AM device having a polymersustained alignment mode, a composition having positive or negativedielectric anisotropy is used. An example of a liquid crystalcomposition having negative dielectric anisotropy is disclosed in Patentliterature Nos. 1 to 4 described below.

CITATION LIST Patent Literature

Patent literature No. 1: JP 2008-88165 A.

Patent literature No. 2: JP 2009-35630 A.

Patent literature No. 3: JP 2010-503733 A.

Patent literature No. 4: JP 2000-53602 A.

SUMMARY OF INVENTION Technical Problem

One of aims of the invention is to provide a liquid crystal compositionsatisfying at least one of characteristics such as high maximumtemperature of a nematic phase, low minimum temperature of the nematicphase, small viscosity, suitable optical anisotropy, large negativedielectric anisotropy, large specific resistance, high stability toultraviolet light and high stability to heat. Another aim is to providea liquid crystal composition having a suitable balance regarding atleast two of the characteristics. Another aim is to provide a liquidcrystal display device including such a composition. Another aim is toprovide an AM device having characteristics such as a short responsetime, a large voltage holding ratio, low threshold voltage, a largecontrast ratio and a long service life.

Solution to Problem

The invention concerns a liquid crystal composition that has negativedielectric anisotropy, and contains at least one compound selected fromthe group of compounds represented by formula (1) as a first component,at least one compound selected from the group of compounds representedby formula (2) as a second component and a compound represented byformula (3) as a third component, and a liquid crystal display deviceincluding the composition:

wherein, in formula (1) and formula (2), R¹ is alkenyl having 2 to 12carbons, R², R³ and R⁴ are independently alkyl having 1 to 12 carbons,alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons,alkenyloxy having 2 to 12 carbons, or alkyl having 1 to 12 carbons inwhich at least one hydrogen is replaced by fluorine or chlorine; ring Aand ring C are independently 1,4-cyclohexylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine; ring D and ringF are independently 1,4-cyclohexylene, 1,4-cyclohexenylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine, in which atleast one of ring D and ring F is 1,4-cyclohexenylene; ring B is2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl; ring E is 2,3-difluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl; Z¹, Z², Z³ and Z⁴ are independently asingle bond, ethylene, carbonyloxy or methyleneoxy; a is 1, 2 or 3; b is0 or 1; a sum of a and b is 3 or less; c is 1, 2 or 3; d is 0 or 1; anda sum of c and d is 3 or less.

Advantageous Effects of Invention

One of advantages of the invention is a liquid crystal compositionsatisfying at least one of characteristics such as high maximumtemperature of a nematic phase, low minimum temperature of the nematicphase, small viscosity, suitable optical anisotropy, large negativedielectric anisotropy, large specific resistance, high stability toultraviolet light and high stability to heat. Another advantage is aliquid crystal composition having a suitable balance regarding at leasttwo of the characteristics. Another advantage is a liquid crystaldisplay device including such a composition. Another advantage is an AMdevice having characteristics such as a short response time, a largevoltage holding ratio, low threshold voltage, a large contrast ratio anda long service life.

DESCRIPTION OF EMBODIMENTS

Usage of terms herein is as described below. Terms “liquid crystalcomposition” and “liquid crystal display device” may be occasionallyabbreviated as “composition” and “device,” respectively. “Liquid crystaldisplay device” is a generic term for a liquid crystal display panel anda liquid crystal display module. “Liquid crystal compound” is a genericterm for a compound having a liquid crystal phase such as a nematicphase and a smectic phase, and a compound having no liquid crystal phasebut to be mixed with the composition for the purpose of adjustingcharacteristics such as a temperature range of the nematic phase,viscosity and dielectric anisotropy. The compound has a six-memberedring such as 1,4-cyclohexylene and 1,4-phenylene, and has rod-likemolecular structure. “Polymerizable compound” is a compound to be addedfor the purpose of forming a polymer in the composition.

The liquid crystal composition is prepared by mixing a plurality ofliquid crystal compounds. A proportion (content) of the liquid crystalcompounds is expressed in terms of weight percent (% by weight) based onthe weight of the liquid crystal composition. An additive such as anoptically active compound, an antioxidant, an ultraviolet lightabsorber, a dye, an antifoaming agent, the polymerizable compound, apolymerization initiator and a polymerization inhibitor is added to theliquid crystal composition when necessary. A proportion (amount ofaddition) of the additive is expressed in terms of weight percent (% byweight) based on the weight of the liquid crystal composition in amanner similar to the proportion of the liquid crystal compound. Weightparts per million (ppm) may be occasionally used. A proportion of thepolymerization initiator and the polymerization inhibitor isexceptionally expressed based on the weight of the polymerizablecompound.

“Maximum temperature of the nematic phase” may be occasionallyabbreviated as “maximum temperature.” “Minimum temperature of thenematic phase” may be occasionally abbreviated as “minimum temperature.”An expression “having large specific resistance” means that thecomposition has large specific resistance at room temperature and alsoat a temperature close to the maximum temperature of the nematic phasein an initial stage, and the composition has the large specificresistance at room temperature and also at a temperature close to themaximum temperature of the nematic phase even after the device has beenused for a long period of time. An expression “having a large voltageholding ratio” means that the device has a large voltage holding ratioat room temperature and also at a temperature close to the maximumtemperature of the nematic phase in the initial stage, and the devicehas the large voltage holding ratio at room temperature and also at atemperature close to the maximum temperature of the nematic phase evenafter the device has been used for a long period of time. An expression“increase the dielectric anisotropy” means that a value of dielectricanisotropy positively increases in a composition having positivedielectric anisotropy, and the value of dielectric anisotropy negativelyincreases in a composition having negative dielectric anisotropy.

A compound represented by formula (1) may be occasionally abbreviated as“compound (1).” At least one compound selected from the group ofcompounds represented by formula (2) may be occasionally abbreviated as“compound (2).” “Compound (1)” means one compound, a mixture of twocompounds or a mixture of three or more compounds represented by formula(1). A same rule applies also to any other compound represented by anyother formula. An expression “at least one piece of ‘A’” means that thenumber of ‘A’ is arbitrary. An expression “at least one piece of ‘A’ maybe replaced by ‘B’” means that, when the number of ‘A’ is 1, a positionof ‘A’ is arbitrary, and also when the number of ‘A’ is 2 or more,positions thereof can be selected without restriction. A same ruleapplies also to an expression “at least one piece of ‘A’ is replaced by‘B’.”

A symbol of terminal group R¹ is used in a plurality of compounds inchemical formulas of component compounds. In the compounds, two groupsrepresented by two pieces of arbitrary R¹ may be identical or different.For example, in one case, R¹ of compound (1-1) is ethyl and R¹ ofcompound (1-2) is ethyl. In another case, R¹ of compound (1-1) is ethyland R of compound (1-2) is propyl. A same rule applies also to a symbolof any other terminal group or the like. In formula (4), when e is 2,two of ring G exists. In the compound, two rings represented by two ofring G may be identical or different. A same rule applies also to two ofarbitrary ring G when e is larger than 2. A same rule applies also to asymbol of Z¹, ring D or the like. A same rule applies also to such acase where two pieces of -Sp²-P⁵ exists in compound (6-27)

Symbol A, B, C or the like surrounded by a hexagonal shape correspondsto a six-membered ring such as ring A, ring B and ring C, respectively.In compound (6), the hexagonal shape represents a six-membered ring or afused ring. An oblique line crossing the hexagonal shape represents thatarbitrary hydrogen on the ring may be replaced by -Sp¹-P¹ group or thelike. A subscript such as h represents the number of groups to bereplaced. When the subscript is 0, no such replacement exists. When h is2 or more, a plurality of pieces of -Sp¹-P¹ exist on ring K. Theplurality of groups represented by -Sp¹-P¹ may be identical ordifferent.

Then, 2-fluoro-1,4-phenylene means two divalent groups described below.In a chemical formula, fluorine may be leftward (L) or rightward (R). Asame rule applies also to an asymmetrical divalent group derived from aring such as tetrahydropyran-2, 5-diyl. A same rule applies also to adivalent bonding group such as carbonyloxy (—COO— or —OCO—).

The invention includes items described below.

Item 1. A liquid crystal composition that has negative dielectricanisotropy, and contains at least one compound selected from the groupof compounds represented by formula (1) as a first component, at leastone compound selected from the group of compounds represented by formula(2) as a second component and a compound represented by formula (3) as athird component:

wherein, in formula (1) and formula (2), R¹ is alkenyl having 2 to 12carbons, R², R³ and R⁴ are independently alkyl having 1 to 12 carbons,alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons,alkenyloxy having 2 to 12 carbons, or alkyl having 1 to 12 carbons inwhich at least one hydrogen is replaced by fluorine or chlorine; ring Aand ring C are independently 1,4-cyclohexylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine; ring D and ringF are independently 1,4-cyclohexylene, 1,4-cyclohexenylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine, in which atleast one of ring D and ring F is 1,4-cyclohexenylene; ring B is2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl; ring E is 2,3-difluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl; Z¹, Z², Z³ and Z⁴ are independently asingle bond, ethylene, carbonyloxy or methyleneoxy; a is 1, 2 or 3; b is0 or 1; a sum of a and b is 3 or less; c is 1, 2 or 3; d is 0 or 1; anda sum of c and d is 3 or less.

Item 2. The liquid crystal composition according to item 1, containingat least one compound selected from the group of compounds representedby formula (1-1) to formula (1-17) as the first component:

wherein, in formula (1-1) to formula (1-17), R¹ is alkenyl having 2 to12 carbons, R² is alkyl having 1 to 12 carbons, alkoxy having 1 to 12carbons, alkenyl having 2 to 12 carbons, alkenyloxy having 2 to 12carbons, or alkyl having 1 to 12 carbons in which at least one hydrogenis replaced by fluorine or chlorine.

Item 3. The liquid crystal composition according to either item 1 or 2,containing at least one compound selected from the group of compoundsrepresented by formula (2-1) to formula (2-5) as the second component:

wherein, in formula (2-1) to formula (2-5), R³ and R⁴ are independentlyalkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenylhaving 2 to 12 carbons, alkenyloxy having 2 to 12 carbons, or alkylhaving 1 to 12 carbons in which at least one hydrogen is replaced byfluorine or chlorine.

Item 4. The liquid crystal composition according to any one of items 1to 3, wherein a proportion of the first component is in the range of 5%by weight to 60% by weight, a proportion of the second component is inthe range of 5% by weight to 50% by weight, and a proportion of thethird component is in the range of 5% by weight to 35% by weight, basedon the weight of the liquid crystal composition.

Item 5. The liquid crystal composition according to any one of items 1to 4, containing at least one compound selected from the group ofcompounds represented by formula (4) as a fourth component:

wherein, in formula (4), R⁵ and R⁶ are independently alkyl having 1 to12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12carbons, alkyl having 1 to 12 carbons in which at least one hydrogen isreplaced by fluorine or chlorine, or alkenyl having 2 to 12 carbons inwhich at least one hydrogen is replaced by fluorine or chlorine; ring Gand ring I are independently 1,4-cyclohexylene, 1,4-phenylene,2-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene; Z⁵ is a singlebond, ethylene or carbonyloxy; e is 1, 2 or 3; and when e is 1, ring Iis 1,4-phenylene.

Item 6. The liquid crystal composition according to any one of items 1to 5, containing at least one compound selected from the group ofcompounds represented by formula (4-1) to formula (4-12) as the fourthcomponent:

wherein, in formula (4-1) to formula (4-12), R⁵ and R⁶ are independentlyalkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenylhaving 2 to 12 carbons, alkyl having 1 to 12 carbons in which at leastone hydrogen is replaced by fluorine or chlorine, or alkenyl having 2 to12 carbons in which at least one hydrogen is replaced by fluorine orchlorine.

Item 7. The liquid crystal composition according to item 5 or 6, whereina proportion of the fourth component is in the range of 5% by weight to40% by weight based on the weight of the liquid crystal composition.

Item 8. The liquid crystal composition according to any one of items 1to 7, containing at least one compound selected from the group ofcompounds represented by formula (5) as a fifth component:

wherein, in formula (5), R⁷ and R⁸ are independently alkyl having 1 to12 carbons, alkoxy having 1 to 12 carbons, or alkyl having 1 to 12carbons in which at least one hydrogen is replaced by fluorine orchlorine; ring N and ring P are independently 1,4-cyclohexylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine; ring Q is2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7, 8-difluorochroman-2, 6-diyl; Z⁶ and Z⁷ are independently a singlebond, ethylene, carbonyloxy or methyleneoxy; p is 1, 2 or 3; q is 0 or1; and a sum of p and q is 3 or less.

Item 9. The liquid crystal composition according to any one of items 1to 8, containing at least one compound selected from the group ofcompounds represented by formula (5-1) to formula (5-17) as the fifthcomponent:

wherein, in formula (5-1) to formula (5-17), R⁷ and R⁸ are independentlyalkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, or alkylhaving 1 to 12 carbons in which at least one hydrogen is replaced byfluorine or chlorine.

Item 10. The liquid crystal composition according to item 8 or 9,wherein a proportion of the fifth component is in the range of 5% byweight to 50% by weight based on the weight of the liquid crystalcomposition.

Item 11. The liquid crystal composition according to any one of items 1to 10, containing at least one polymerizable compound selected from thegroup of compounds represented by formula (6) as an additive component:

wherein, in formula (6), ring K and ring M are independently cyclohexyl,cyclohexenyl, phenyl, 1-naphthyl, 2-naphthyl, tetrahydropyran-2-yl,1,3-dioxane-2-yl, pyrimidine-2-yl or pyridine-2-yl, and in the rings, atleast one hydrogen may be replaced by fluorine, chlorine, alkyl having 1to 12 carbons, alkoxy having 1 to 12 carbons, or alkyl having 1 to 12carbons in which at least one hydrogen is replaced by fluorine orchlorine; ring L is 1,4-cyclohexylene, 1,4-cyclohexenylene,1,4-phenylene, naphthalene-1,2-diyl, naphthalene-1,3-diyl,naphthalene-1,4-diyl, naphthalene-1,5-diyl, naphthalene-1,6-diyl,naphthalene-1,7-diyl, naphthalene-1,8-diyl, naphthalene-2,3-diyl,naphthalene-2,6-diyl, naphthalene-2,7-diyl, tetrahydropyran-2,5-diyl,1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl or pyridine-2,5-diyl, and inthe rings, at least one hydrogen may be replaced by fluorine, chlorine,alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, or alkylhaving 1 to 12 carbons in which at least one hydrogen is replaced byfluorine or chlorine; Z⁸ and Z⁹ are independently a single bond oralkylene having 1 to 10 carbons, and in the alkylene, at least one pieceof —CH₂— may be replaced by —O—, —CO—, —COO— or —OCO—, and at least onepiece of —CH₂—CH₂— may be replaced by —CH═CH—, —C(CH₃)═CH—, —CH═C(CH₃)—or —C(CH₃)═C(CH₃)—, and in the groups, at least one hydrogen may bereplaced by fluorine or chlorine; P¹, P² and P³ are independently apolymerizable group; Sp¹, Sp² and Sp³ are independently a single bond oralkylene having 1 to 10 carbons, and in the alkylene, at least one pieceof —CH₂— may be replaced by —O—, —COO—, —OCO— or —OCOO—, and at leastone piece of —CH₂—CH₂— may be replaced by —CH═CH— or —C≡C—, and in thegroups, at least one hydrogen may be replaced by fluorine or chlorine; gis 0, 1 or 2; h, j and k are independently 0, 1, 2, 3 or 4; and a sum ofh, j and k is 1 or more.

Item 12. The liquid crystal composition according to item 11, wherein,in formula (6), P¹, P² and P³ are independently a polymerizable groupselected from the group of groups represented by formula (P-1) toformula (P-5):

wherein, in formula (P-1) to formula (P-5), M¹, M² and M³ areindependently hydrogen, fluorine, alkyl having 1 to 5 carbons, or alkylhaving 1 to 5 carbons in which at least one hydrogen is replaced byfluorine or chlorine.

Item 13. The liquid crystal composition according to any one of items 1to 12, containing at least one polymerizable compound selected from thegroup of compounds represented by formula (6-1) to formula (6-27) as theadditive component:

wherein, in formula (6-1) to formula (6-27), P⁴, P⁵ and P⁶ areindependently a polymerizable group selected from the group of groupsrepresented by formula (P-1) to formula (P-3);

wherein, in formula (P-1) to formula (P-3), M¹, M² and M³ areindependently hydrogen, fluorine, alkyl having 1 to 5 carbons, or alkylhaving 1 to 5 carbons in which at least one hydrogen is replaced byfluorine or chlorine; and in formula (6-1) to formula (6-27), Sp¹, Sp²and Sp³ are independently a single bond or alkylene having 1 to 10carbons, and in the alkylene, at least one piece of —CH₂— may bereplaced by —O—, —COO—, —OCO— or —OCOO—, and at least one piece of—CH₂—CH₂— may be replaced by —CH═CH— or —C≡C—, and in the groups, atleast one hydrogen may be replaced by fluorine or chlorine.

Item 14. The liquid crystal composition according to any one of items 11to 13, wherein a proportion of addition of the additive component is inthe range of 0.03% by weight to 10% by weight based on the weight of theliquid crystal composition.

Item 15. A liquid crystal display device, including the liquid crystalcomposition according to any one of items 1 to 14.

Item 16. The liquid crystal display device according to item 15, whereinan operating mode in the liquid crystal display device includes an IPSmode, a VA mode, an FFS mode or an FPA mode, and a driving mode in theliquid crystal display device includes an active matrix mode.

Item 17. A polymer sustained alignment mode liquid crystal displaydevice, wherein the liquid crystal display device includes the liquidcrystal composition according to any one of items 11 to 14, or thepolymerizable compound in the liquid crystal composition is polymerized.

Item 18. Use of the liquid crystal composition according to any one ofitems 1 to 14 in a liquid crystal display device.

Item 19. Use of the liquid crystal composition according to any one ofitems 11 to 14 in a polymer sustained alignment mode liquid crystaldisplay device.

The invention further includes the following items: (a) the composition,further containing at least one of additives such as an optically activecompound, an antioxidant, an ultraviolet light absorber, a dye, anantifoaming agent, a polymerizable compound, a polymerization initiatorand a polymerization inhibitor; (b) an AM device including thecomposition; (c) a polymer sustained alignment (PSA) mode AM deviceincluding the composition further containing the polymerizable compound;(d) the polymer sustained alignment (PSA) mode AM device, wherein thedevice includes the composition, and the polymerizable compound in thecomposition is polymerized; (e) a device including the composition andhaving the PC mode, the TN mode, the STN mode, the ECB mode, the OCBmode, the IPS mode, the VA mode, the FFS mode or the FPA mode; (f) atransmissive device including the composition; (g) use of thecomposition as the composition having the nematic phase; and (h) use asan optically active composition by adding the optically active compoundto the composition.

The composition of the invention will be described in the followingorder. First, a constitution of the component compounds in thecomposition will be described. Second, main characteristics of thecomponent compounds and main effects of the compounds on the compositionwill be described. Third, a combination of components in thecomposition, a preferred proportion of the components and the basisthereof will be described. Fourth, a preferred embodiment of thecomponent compounds will be described. Fifth, a preferred componentcompound will be described. Sixth, an additive that may be added to thecomposition will be described. Seventh, methods for synthesizing thecomponent compounds will be described. Last, an application of thecomposition will be described.

First, the constitution of the component compounds in the compositionwill be described. The composition of the invention is classified intocomposition A and composition B. Composition A may further contain anyother liquid crystal compound, an additive or the like in addition tothe liquid crystal compound selected from compound (1), compound (2),compound (3), compound (4) and compound (5). An expression “any otherliquid crystal compound” means a liquid crystal compound different fromcompound (1), compound (2), compound (3), compound (4) and compound (5).Such a compound is mixed with the composition for the purpose of furtheradjusting the characteristics. The additive includes the opticallyactive compound, the antioxidant, the ultraviolet light absorber, thedye, the antifoaming agent, the polymerizable compound, thepolymerization initiator and the polymerization inhibitor.

Composition B consists essentially of liquid crystal compounds selectedfrom compound (1), compound (2), compound (3), compound (4) and compound(5). An expression “essentially” means that the composition may containthe additive, but contains no any other liquid crystal compound.Composition B has a smaller number of components than composition A has.Composition B is preferred to composition A in view of cost reduction.Composition A is preferred to composition B in view of possibility offurther adjusting the characteristics by mixing any other liquid crystalcompound.

Second, the main characteristics of the component compounds and the maineffects of the compounds on the characteristics of the composition willbe described. The main characteristics of the component compounds aresummarized in Table 2 on the basis of advantageous effects of theinvention. In Table 2, a symbol L stands for “large” or “high,” a symbolM stands for “medium” and a symbol S stands for “small” or “low.” Thesymbols L, M and S represent a classification based on a qualitativecomparison among the component compounds, and 0 (zero) means that “avalue is zero” or “a value is nearly zero.”

TABLE 2 Characteristics of Compounds Com- Com- Com- Com- Com- poundpound pound pound pound Compounds (1) (2) (3) (4) (5) Maximum S to L Sto L M S to L S to L temperature Viscosity M to L M to L S S to M M to LOptical anisotropy M to L M to L S S to L M to L Dielectric anisotropy Mto L¹⁾ M to L¹⁾ 0 0 M to L¹⁾ Specific resistance L L L L L ¹⁾A compoundhaving negative dielectric anisotropy.

Upon mixing the component compounds with the composition, the maineffects of the component compounds on the characteristics of thecomposition are as described below. Compound (1) increases thedielectric anisotropy. Compound (2) decreases the minimum temperature.Compound (3) decreases the viscosity. Compound (4) increases the maximumtemperature or decreases the viscosity. Compound (5) increases thedielectric anisotropy and decreases the minimum temperature. Compound(6) is polymerized to give a polymer, and the polymer shortens aresponse time in the device, and improves image persistence.

Third, the combination of components in the composition, the preferredproportion of the component compounds and the basis thereof will bedescribed. A preferred combination of the components in the compositionincludes a combination of the first component, the second component andthe third component, a combination of the first component, the secondcomponent, the third component and the fourth component, a combinationof the first component, the second component, the third component andthe fifth component, a combination of the first component, the secondcomponent, the third component and the additive component, a combinationof the first component, the second component, the third component, thefourth component and the fifth component, a combination of the firstcomponent, the second component, the third component, the fourthcomponent and the additive component, a combination of the firstcomponent, the second component, the third component, the fifthcomponent and the additive component, or a combination of the firstcomponent, the second component, the third component, the fourthcomponent, the fifth component and the additive component. A furtherpreferred combination includes a combination of the first component, thesecond component, the third component and the fifth component, acombination of the first component, the second component, the thirdcomponent, the fifth component and the additive component, a combinationof the first component, the second component, the third component, thefourth component and the fifth component, or a combination of the firstcomponent, the second component, the third component, the fourthcomponent, the fifth component and the additive component.

A preferred proportion of the first component is about 5% by weight ormore for increasing the dielectric anisotropy, and about 60% by weightor less for decreasing the minimum temperature. A further preferredproportion is in the range of about 5% by weight to about 55% by weight.A particularly preferred proportion is in the range of about 10% byweight to about 50% by weight based thereon.

A preferred proportion of the second component is about 5% by weight ormore for decreasing the minimum temperature, and about 50% by weight orless for decreasing the viscosity. A further preferred proportion is inthe range of about 10% by weight to about 45% by weight. A particularlypreferred proportion is in the range of about 10% by weight to about 40%by weight based thereon.

A preferred proportion of the third component is about 5% by weight ormore for decreasing the viscosity, and about 35% by weight or less forincreasing the dielectric anisotropy. A further preferred proportion isin the range of about 10% by weight to about 35% by weight. Aparticularly preferred proportion is in the range of about 15% by weightto about 30% by weight based thereon.

A preferred proportion of the fourth component is about 5% by weight ormore for increasing the maximum temperature or decreasing the viscosity,and about 40% by weight or less for increasing the dielectricanisotropy. A further preferred proportion is in the range of about 5%by weight to about 35% by weight. A particularly preferred proportion isin the range of about 10% by weight to about 25% by weight basedthereon.

A preferred proportion of the fifth component is about 5% by weight ormore for increasing the dielectric anisotropy, and about 50% by weightor less for decreasing the minimum temperature. A further preferredproportion is in the range of about 5% by weight to about 45% by weight.A particularly preferred proportion is in the range of about 10% byweight to about 40% by weight based thereon.

Compound (6) is added to the composition for the purpose of adapting thecomposition to the polymer sustained alignment mode device. A preferredproportion of the additive component is about 0.03% by weight or morefor aligning the liquid crystal molecules, and about 10% by weight orless for preventing poor display in the device. A further preferredproportion is in the range of about 0.1% by weight to about 2% byweight. A particularly preferred proportion is in the range of about0.2% by weight to about 1.0% by weight based thereon.

Fourth, the preferred embodiment of the component compounds will bedescribed. In formula (1), formula (2), formula (4) and formula (5), R¹is alkenyl having 2 to 12 carbons. R², R³ and R⁴ are independently alkylhaving 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2to 12 carbons, alkenyloxy having 2 to 12 carbons, or alkyl having 1 to12 carbons in which at least one hydrogen is replaced by fluorine orchlorine. Preferred R², R³ or R⁴ is alkyl having 1 to 12 carbons forincreasing the stability, and alkoxy having 1 to 12 carbons forincreasing the dielectric anisotropy. R⁵ and R⁶ are independently alkylhaving 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2to 12 carbons, alkyl having 1 to 12 carbons in which at least onehydrogen is replaced by fluorine or chlorine, or alkenyl having 2 to 12carbons in which at least one hydrogen is replaced by fluorine orchlorine. Preferred R⁵ or R⁶ is alkenyl having 2 to 12 carbons fordecreasing the viscosity, and alkyl having 1 to 12 carbons forincreasing the stability. R⁷ and R⁸ are independently alkyl having 1 to12 carbons, alkoxy having 1 to 12 carbons, or alkyl having 1 to 12carbons in which at least one hydrogen is replaced by fluorine orchlorine. Preferred R⁷ or R⁸ is alkyl having 1 to 12 carbons forincreasing the stability, and alkoxy having 1 to 12 carbons forincreasing the dielectric anisotropy. Alkyl is straight-chain alkyl orbranched-chain alkyl, but includes no cyclic alkyl. Straight-chain alkylis preferred to branched-chain alkyl. A same rule applies also to aterminal group such as alkoxy and alkenyl.

Preferred alkyl is methyl, ethyl, propyl, butyl, pentyl, hexyl, heptylor octyl. Further preferred alkyl is ethyl, propyl, butyl, pentyl orheptyl for decreasing the viscosity.

Preferred alkoxy is methoxy, ethoxy, propoxy, butoxy, pentyloxy,hexyloxy or heptyloxy. Further preferred alkoxy is methoxy or ethoxy fordecreasing the viscosity.

Preferred alkenyl is vinyl, 1-propenyl, 2-propenyl, l-butenyl,2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl,1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl or 5-hexenyl. Furtherpreferred alkenyl is vinyl, 1-propenyl, 3-butenyl or 3-pentenyl fordecreasing the viscosity. A preferred configuration of —CH═CH— in thealkenyl depends on a position of a double bond. Trans is preferred inalkenyl such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyland 3-hexenyl for decreasing the viscosity, for instance. Cis ispreferred in alkenyl such as 2-butenyl, 2-pentenyl and 2-hexenyl.

Preferred examples of alkyl in which at least one hydrogen is replacedby fluorine or chlorine are fluoromethyl, 2-fluoroethyl, 3-fluoropropyl,4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl, 7-fluoroheptyl or8-fluorooctyl. Further preferred examples are 2-fluoroethyl,3-fluoropropyl, 4-fluorobutyl or 5-fluoropentyl for increasing thedielectric anisotropy.

Preferred examples of alkenyl in which at least one hydrogen is replacedby fluorine or chlorine are 2,2-difluorovinyl, 3,3-difluoro-2-propenyl,4,4-difluoro-3-butenyl, 5,5-difluoro-4-pentenyl or6,6-difluoro-5-hexenyl. Further preferred examples are 2,2-difluorovinylor 4,4-difluoro-3-butenyl for decreasing the viscosity.

Ring A, ring C, ring N and ring P are independently 1,4-cyclohexylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine. Preferred ringA, ring C, ring N or ring P is 1,4-cyclohexylene for decreasing theviscosity or increasing the maximum temperature, and 1,4-phenylene fordecreasing the minimum temperature. With regard to a configuration of1,4-cyclohexylene, trans is preferred to cis for increasing the maximumtemperature. Tetrahydropyran-2,5-diyl includes:

Ring D and ring F are independently 1,4-cyclohexylene,1,4-cyclohexenylene, tetrahydropyran-2,5-diyl, 1,4-phenylene, or1,4-phenylene in which at least one hydrogen is replaced by fluorine orchlorine, and in which at least one of ring D and ring F is1,4-cyclohexenylene.

Ring B and ring Q are independently 2,3-difluoro-1,4-phenylene,2-chloro-3-fluoro-1,4-phenylene, 2,3-difluoro-5-methyl-1,4-phenylene,3,4,5-trifluoronaphthalene-2,6-diyl or 7,8-difluorochroman-2,6-diyl.Preferred ring B or ring Q is 2,3-difluoro-1,4-phenylene for decreasingthe viscosity, 2-chloro-3-fluoro-1,4-phenylene for decreasing theoptical anisotropy, and 7,8-difluorochroman-2,6-diyl for increasing thedielectric anisotropy.

Ring E is 2,3-difluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl. Preferred ring E is2,3-difluoro-1,4-phenylene for decreasing the viscosity, and7,8-difluorochroman-2,6-diyl for increasing the dielectric anisotropy.

Ring G and ring I are independently 1,4-cyclohexylene, 1,4-phenylene,2-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene. Preferred ring Gor ring I is 1,4-cyclohexylene for decreasing the viscosity orincreasing the maximum temperature, and 1,4-phenylene for decreasing theminimum temperature.

Z¹, Z², Z³, Z⁴, Z⁶ and Z⁷ are independently a single bond, ethylene,carbonyloxy or methyleneoxy. Preferred Z¹, Z², Z³, Z⁴, Z⁶ or Z⁷ is asingle bond for decreasing the viscosity, ethylene for decreasing theminimum temperature, and methyleneoxy for increasing the dielectricanisotropy. Z⁵ is a single bond, ethylene or carbonyloxy. Preferred Z⁵is a single bond for increasing the stability.

Then, a is 1, 2 or 3, b is 0 or 1, and a sum of a and b is 3 or less.Preferred a is 1 for decreasing the viscosity, and 2 or 3 for increasingthe maximum temperature. Preferred b is 0 for decreasing the viscosity,and 1 for decreasing the minimum temperature. Then, c is 1, 2 or 3, d is0 or 1, and a sum of c and d is 3 or less. Preferred c is 1 fordecreasing the viscosity, and 2 or 3 for increasing the maximumtemperature. Preferred d is 0 for decreasing the viscosity, and 1 fordecreasing the minimum temperature. Then, e is 1, 2 or 3. Preferred e is1 for decreasing the viscosity, and 2 or 3 for increasing the maximumtemperature. Then, p is 1, 2 or 3, q is 0 or 1, and a sum of p and q is3 or less. Preferred p is 1 for decreasing the viscosity, and 2 or 3 forincreasing the maximum temperature. Preferred q is 0 for decreasing theviscosity, and 1 for decreasing the minimum temperature.

In formula (6), P¹, P² and P³ are independently a polymerizable group.Preferred P¹, P² or P³ is a polymerizable group selected from the groupof groups represented by formula (P-1) to formula (P-5). Furtherpreferred P¹, P² or P³ is a group represented by formula (P-1), formula(P-2) or formula (P-3). Particularly preferred P¹, P² or P³ is a grouprepresented by formula (P-1) or formula (P-2). Most preferred P¹, P² orP³ is a group represented by formula (P-1). A preferred grouprepresented by formula (P-1) is —OCO—CH═CH₂ or —OCO—C(CH₃)═CH₂. A wavyline in formula (P-1) to formula (P-5) represents a site to form abonding.

In formula (P-1) to formula (P-5), M¹, M² and M³ are independentlyhydrogen, fluorine, alkyl having 1 to 5 carbons, or alkyl having 1 to 5carbons in which at least one hydrogen is replaced by fluorine orchlorine. Preferred M¹, M² or M³ is hydrogen or methyl for increasingreactivity. Further preferred M¹ is hydrogen or methyl, and furtherpreferred M² or M³ is hydrogen.

Sp¹, Sp² and Sp³ are independently a single bond or alkylene having 1 to10 carbons, and in the alkylene, at least one piece of —CH₂— may bereplaced by —O—, —COO—, —OCO— or —OCOO—, and at least one piece of—CH₂—CH₂— may be replaced by —CH═CH— or —C≡C—, and in the groups, atleast one hydrogen may be replaced by fluorine or chlorine. PreferredSp¹, Sp² or Sp³ is a single bond, —CH₂CH₂—, —CH₂O—, —OCH₂—, —COO—,—OCO—, —CO—CH═CH— or —CH═CH—CO—. Further preferred Sp¹, Sp² or Sp³ is asingle bond.

Ring K and ring M are independently cyclohexyl, cyclohexenyl, phenyl,1-naphthyl, 2-naphthyl, tetrahydropyran-2-yl, 1, 3-dioxane-2-yl,pyrimidine-2-yl or pyridine-2-yl, and in the rings, at least onehydrogen may be replaced by fluorine, chlorine, alkyl having 1 to 12carbons, alkoxy having 1 to 12 carbons, or alkyl having 1 to 12 carbonsin which at least one hydrogen is replaced by fluorine or chlorine.Preferred ring K or ring M is phenyl. Ring L is 1,4-cyclohexylene,1,4-cyclohexenylene, 1,4-phenylene, naphthalene-1,2-diyl,naphthalene-1,3-diyl, naphthalene-1,4-diyl, naphthalene-1,5-diyl,naphthalene-1,6-diyl, naphthalene-1,7-diyl, naphthalene-1,8-diyl,naphthalene-2,3-diyl, naphthalene-2,6-diyl, naphthalene-2,7-diyl,tetrahydropyran-2,5-diyl, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl orpyridine-2,5-diyl, and in the rings, at least one hydrogen may bereplaced by fluorine, chlorine, alkyl having 1 to 12 carbons, alkoxyhaving 1 to 12 carbons, or alkyl having 1 to 12 carbons in which atleast one hydrogen is replaced by fluorine or chlorine. Preferred ring Lis 1,4-phenylene or 2-fluoro-1,4-phenylene.

Z⁸ and Z⁹ are independently a single bond or alkylene having 1 to 10carbons, and in the alkylene, at least one piece of —CH₂— may bereplaced by —O—, —CO—, —COO— or —OCO—, and at least one piece of—CH₂—CH₂— may be replaced by —CH═CH—, —C(CH₃)═CH—, —CH═C(CH₃)— or—C(CH₃)═C(CH₃)—, and in the groups, at least one hydrogen may bereplaced by fluorine or chlorine. Preferred Z⁸ or Z⁹ is a single bond,—CH₂CH₂—, —CH₂O—, —OCH₂—, —COO— or —OCO—. Further preferred Z⁸ or Z⁹ isa single bond.

Then, g is 0, 1 or 2. Preferred g is 0 or 1. Then, h, j and k areindependently 0, 1, 2, 3 or 4, and a sum of h, j and k is 1 or more.Preferred h, j or k is 1 or 2.

Fifth, the preferred component compound will be described. Preferredcompound (1) includes compound (1-1) to compound (1-17) described initem 2. In the compounds, at least one of the first componentspreferably includes compound (1-1), compound (1-2), compound (1-3),compound (1-4), compound (1-6), compound (1-7), compound (1-8) orcompound (1-10). At least two of the first components preferablyincludes a combination of compound (1-1) and compound (1-6), acombination of compound (1-1) and compound (1-10), a combination ofcompound (1-3) and compound (1-6), a combination of compound (1-3) andcompound (1-10), a combination of compound (1-4) and compound (1-6), ora combination of compound (1-4) and compound (1-10).

Preferred compound (2) includes compound (2-1) to compound (2-5)described in item 3. In the compounds, at least one of the secondcomponents preferably includes compound (2-1), compound (2-2) orcompound (2-4). At least two of the second components preferablyincludes a combination of compound (2-1) and compound (2-2).

Preferred compound (4) includes compound (4-1) to compound (4-12)described in item 6. In the compounds, at least one of the fourthcomponents preferably includes compound (4-2), compound (4-4), compound(4-5) or compound (4-6). At least two of the fourth componentspreferably includes a combination of compound (4-2) and compound (4-4),or a combination of compound (4-2) and compound (4-6).

Preferred compound (5) includes compound (5-1) to compound (5-17)described in item 9. In the compounds, at least one of the fifthcomponents preferably includes compound (5-1), compound (5-2), compound(5-3), compound (5-4), compound (5-6), compound (5-7), compound (5-8) orcompound (5-10). At least two of the fifth components preferablyincludes a combination of compound (5-1) and compound (5-6), acombination of compound (5-1) and compound (5-10), a combination ofcompound (5-3) and compound (5-6), a combination of compound (5-3) andcompound (5-10), a combination of compound (5-4) and compound (5-6), ora combination of compound (5-4) and compound (5-10).

Preferred compound (6) includes compound (6-1) to compound (6-27)described in item 13. In the compounds, at least one of the additivecomponents preferably includes compound (6-1), compound (6-2), compound(6-24), compound (6-25), compound (6-26) or compound (6-27). At leasttwo of the additive components preferably includes a combination ofcompound (6-1) and compound (6-2), a combination of compound (6-1) andcompound (6-18), a combination of compound (6-2) and compound (6-24), acombination of compound (6-2) and compound (6-25), a combination ofcompound (6-2) and compound (6-26), a combination of compound (6-25) andcompound (6-26), or a combination of compound (6-18) and compound(6-24).

Sixth, the additive that may be added to the composition will bedescribed. Such an additive includes the optically active compound, theantioxidant, the ultraviolet light absorber, the dye, the antifoamingagent, the polymerizable compound, the polymerization initiator and thepolymerization inhibitor. The optically active compound is added to thecomposition for the purpose of inducing a helical structure in liquidcrystal molecules to give a twist angle. Examples of such a compoundinclude compound (7-1) to compound (7-5). A preferred proportion of theoptically active compound is about 5% by weight or less. A furtherpreferred proportion is in the range of about 0.01% by weight to about2% by weight.

The antioxidant is added to the composition for preventing a decrease inthe specific resistance caused by heating in air, or for maintaining alarge voltage holding ratio at room temperature and also at atemperature close to the maximum temperature even after the device hasbeen used for a long period of time. Specific examples of a preferredantioxidant include compound (8) in which n is an integer from 1 to 9.

In compound (8), preferred n is 1, 3, 5, 7 or 9. Further preferred n is7. Compound (8) in which n is 7 is effective in maintaining a largevoltage holding ratio at room temperature and also at a temperatureclose to the maximum temperature even after the device has been used fora long period of time because such compound (8) has small volatility. Apreferred proportion of the antioxidant is about 50 ppm or more forachieving an effect thereof, and about 600 ppm or less for avoiding adecrease in the maximum temperature or an increase in the minimumtemperature. A further preferred proportion is in the range of about 100ppm to about 300 ppm.

Specific examples of a preferred ultraviolet light absorber include abenzophenone derivative, a benzoate derivative and a triazolederivative. A light stabilizer such as an amine having steric hindranceis also preferred. A preferred proportion of the absorber or thestabilizer is about 50 ppm or more for achieving an effect thereof, andabout 10,000 ppm or less for avoiding a decrease in the maximumtemperature or an increase in the minimum temperature. A furtherpreferred proportion is in the range of about 100 ppm to about 10,000ppm.

A dichroic dye such as an azo dye or an anthraquinone dye is added tothe composition to be adapted for a device having a guest host (GH)mode. A preferred proportion of the dye is in the range of about 0.01%by weight to about 10% by weight. The antifoaming agent such as dimethylsilicone oil or methyl phenyl silicone oil is added to the compositionfor preventing foam formation. A preferred proportion of the antifoamingagent is about 1 ppm or more for achieving an effect thereof, and about1,000 ppm or less for preventing poor display. A further preferredproportion is in the range of about 1 ppm to about 500 ppm.

The polymerizable compound is used to be adapted for a polymer sustainedalignment (PSA) mode device. Compound (6) is suitable for the purpose.Any other polymerizable compound that is different from compound (6) maybe added to the composition together with compound (6). In place ofcompound (6), any other polymerizable compound that is different fromcompound (6) may be added to the composition. Specific examples of sucha preferred polymerizable compound include a compound such as acrylate,methacrylate, a vinyl compound, a vinyloxy compound, propenyl ether, anepoxy compound (oxirane, oxetane) and vinyl ketone. Further preferredexamples include an acrylate derivative or a methacrylate derivative. Apreferred proportion of compound (6) is about 10% by weight or morebased on the total weight of the polymerizable compound. A furtherpreferred proportion is about 50% by weight or more. A particularlypreferred proportion is about 80% by weight or more. A most preferredproportion is 100% by weight based thereon.

The polymerizable compound such as compound (6) is polymerized byirradiation with ultraviolet light. The polymerizable compound may bepolymerized in the presence of a suitable initiator such as aphotopolymerization initiator. Suitable conditions for polymerization,suitable types of the initiator and suitable amounts thereof are knownto those skilled in the art and are described in literature. Forexample, Irgacure 651 (registered trademark; BASF), Irgacure 184(registered trademark; BASF) or Darocur 1173 (registered trademark;BASF), each being a photopolymerization initiator, is suitable forradical polymerization. A preferred proportion of thephotopolymerization initiator is in the range of about 0.1% by weight toabout 5% by weight based on the total weight of the polymerizablecompound. A further preferred proportion is in the range of about 1% byweight to about 3% by weight based thereon.

Upon storing the polymerizable compound such as compound (6), thepolymerization inhibitor may be added thereto for preventingpolymerization. The polymerizable compound is ordinarily added to thecomposition without removing the polymerization inhibitor. Specificexamples of the polymerization inhibitor include hydroquinone, ahydroquinone derivative such as methylhydroquinone, 4-t-butylcatechol,4-methoxyphenol and phenothiazine.

Seventh, the methods for synthesizing the component compounds will bedescribed. The compounds can be prepared according to known methods.Examples of the synthetic methods are described. Compound (1-1) isprepared according to the method described in JP 2000-53602 A. Compound(2-2) is prepared according to a method described in JP H2-4723 A.Compound (3) is prepared according to a method described in JP S59-70624A. Compound (4-1) is prepared according to a method described in JPS56-68636 A. Compound (5-1) is prepared according to a method describedin JP H2-503441 A. Compound (6-18) is prepared according to a methoddescribed in JP H7-101900 A. The antioxidant is commercially available.A compound in which n in formula (8) is 1 is available fromSigma-Aldrich Corporation. Compound (8) in which n is 7 or the like isprepared according to a method described in U.S. Pat. No. 3,660,505 B.

Any compounds whose synthetic methods are not described above can beprepared according to the methods described in books such as OrganicSyntheses (John Wiley & Sons, Inc.), Organic Reactions (John Wiley &Sons, Inc.), Comprehensive Organic Synthesis (Pergamon Press) and NewExperimental Chemistry Course (Shin Jikken Kagaku Koza in Japanese)(Maruzen Co., Ltd.). The composition is prepared according to a publiclyknown method using the thus obtained compounds. For example, thecomponent compounds are mixed and dissolved in each other by heating.

Last, the application of the composition will be described. Most of thecompositions have a minimum temperature of about −10° C. or lower, amaximum temperature of about 70° C. or higher, and optical anisotropy inthe range of about 0.07 to about 0.20. A composition having opticalanisotropy in the range of about 0.08 to about 0.25 may be prepared bycontrolling a proportion of the component compounds or by mixing anyother liquid crystal compound. Further, a composition having opticalanisotropy in the range of about 0.10 to about 0.30 may be preparedaccording to the method. A device including the composition has thelarge voltage holding ratio. The composition is suitable for use in theAM device. The composition is particularly suitable for use in atransmissive AM device. The composition can be used as the compositionhaving the nematic phase, and as the optically active composition byadding the optically active compound.

The composition can be used in the AM device. The composition can alsobe used in a PM device. The composition can also be used in the AMdevice and the PM device each having a mode such as the PC mode, the TNmode, the STN mode, the ECB mode, the OCB mode, the IPS mode, the FFSmode, the VA mode and the FPA mode. Use in the AM device having the TNmode, the OCB mode, the IPS mode or the FFS mode is particularlypreferred. In the AM device having the IPS mode or the FFS mode,alignment of liquid crystal molecules when no voltage is applied may beparallel or perpendicular to a glass substrate. The devices may be of areflective type, a transmissive type or a transflective type. Use in thetransmissive device is preferred. The composition can also be used in anamorphous silicon-TFT device or a polycrystal silicon-TFT device. Thecomposition can also be used in a nematic curvilinear aligned phase(NCAP) device prepared by microencapsulating the composition, or apolymer dispersed (PD) device in which a three-dimensionalnetwork-polymer is formed in the composition.

EXAMPLES

The invention will be described in greater detail by way of Examples.However, the invention is not limited by the Examples. The inventionincludes a mixture of a composition in Example 1 and a composition inExample 2. The invention also includes a mixture in which at least twocompositions in Examples were mixed. The thus prepared compound wasidentified by methods such as an NMR analysis. Characteristics of thecompound, the composition and the device were measured by methodsdescribed below.

NMR analysis: For measurement, DRX-500 made by Bruker BioSpinCorporation was used. In ¹H-NMR measurement, a sample was dissolved in adeuterated solvent such as CDCl₃, and measurement was carried out underconditions of room temperature, 500 MHz and 16 times of accumulation.Tetramethylsilane was used as an internal standard. In 19F-NMRmeasurement, CFCl₃ was used as an internal standard, and measurement wascarried out under conditions of 24 times of accumulation. In explainingnuclear magnetic resonance spectra obtained, s, d, t, q, quin, sex and mstand for a singlet, a doublet, a triplet, a quartet, a quintet, asextet and a multiplet, and br being broad, respectively.

Gas chromatographic analysis: For measurement, GC-14B Gas Chromatographmade by Shimadzu Corporation was used. A carrier gas was helium (2 mLper minute). A sample vaporizing chamber and a detector (FID) were setto 280° C. and 300° C., respectively. A capillary column DB-1 (length 30m, bore 0.32 mm, film thickness 0.25 μm; dimethylpolysiloxane as astationary liquid phase; non-polar) made by Agilent Technologies, Inc.was used for separation of component compounds. After the column waskept at 200° C. for 2 minutes, the column was heated to 280° C. at arate of 5° C. per minute. A sample was prepared in an acetone solution(0.1% by weight), and then 1 microliter of the solution was injectedinto the sample vaporizing chamber. A recorder was C-R5A Chromatopacmade by Shimadzu Corporation or the equivalent thereof. The resultinggas chromatogram showed a retention time of a peak and a peak areacorresponding to each of the component compounds.

As a solvent for diluting the sample, chloroform, hexane or the like mayalso be used. The following capillary columns may also be used forseparating component compounds: HP-1 (length 30 m, bore 0.32 mm, filmthickness 0.25 μm) made by Agilent Technologies, Inc., Rtx-1 (length 30m, bore 0.32 mm, film thickness 0.25 μm) made by Restek Corporation andBP-1 (length 30 m, bore 0.32 mm, film thickness 0.25 μm) made by SGEInternational Pty. Ltd. A capillary column CBP1-M50-025 (length 50 m,bore 0.25 mm, film thickness 0.25 μm) made by Shimadzu Corporation mayalso be used for the purpose of preventing an overlap of peaks of thecompounds.

A proportion of liquid crystal compounds contained in the compositionmay be calculated by the method as described below. A mixture of liquidcrystal compounds is detected by gas chromatograph (FID). An area ratioof each peak in the gas chromatogram corresponds to the ratio (weightratio) of the liquid crystal compound. When the capillary columnsdescribed above were used, a correction coefficient of each of theliquid crystal compounds may be regarded as 1 (one). Accordingly, theproportion (% by weight) of the liquid crystal compounds can becalculated from the area ratio of each peak.

Sample for measurement: When characteristics of the composition and thedevice were measured, the composition was used as a sample as was. Uponmeasuring characteristics of a compound, a sample for measurement wasprepared by mixing the compound (15% by weight) with a base liquidcrystal (85% by weight). Values of characteristics of the compound werecalculated, according to an extrapolation method, using values obtainedby measurement. (Extrapolated value)={(measured value of asample)−0.85×(measured value of a base liquid crystal)}/0.15. When asmectic phase (or crystals) precipitates at the ratio thereof at 25° C.,a ratio of the compound to the base liquid crystal was changed step bystep in the order of (10% by weight:90% by weight), (5% by weight:95% byweight) and (1% by weight:99% by weight). Values of maximum temperature,optical anisotropy, viscosity and dielectric anisotropy with regard tothe compound were determined according to the extrapolation method.

A base liquid crystal described below was used. A proportion of thecomponent compound was expressed in terms of weight percent (% byweight).

Measuring method: Characteristics were measured according to the methodsdescribed below. Most of the measuring methods are applied as describedin the Standard of Japan Electronics and Information TechnologyIndustries Association (hereinafter abbreviated as JEITA) (JEITAED-2521B) discussed and established by JEITA, or modified thereon. Nothin film transistor (TFT) was attached to a TN device used formeasurement.

(1) Maximum temperature of nematic phase (NI; ° C.): A sample was placedon a hot plate in a melting point apparatus equipped with a polarizingmicroscope, and heated at a rate of 1° C. per minute. Temperature whenpart of the sample began to change from a nematic phase to an isotropicliquid was measured. A maximum temperature of the nematic phase may beoccasionally abbreviated as “maximum temperature.”

(2) Minimum temperature of nematic phase (T_(C); ° C.): Samples eachhaving a nematic phase were put in glass vials and kept in freezers attemperatures of 0° C., −10° C., −20° C., −30° C. and −40° C. for 10days, and then liquid crystal phases were observed. For example, whenthe sample was maintained in the nematic phase at −20° C. and changed tocrystals or a smectic phase at −30° C., T_(C) was expressed asT_(C)<−20° C. A minimum temperature of the nematic phase may beoccasionally abbreviated as “minimum temperature.”

(3) Viscosity (bulk viscosity; γ1; measured at 20° C.; mPa·s): Formeasurement, a cone-plate (E type) rotational viscometer made by TokyoKeiki Inc. was used.

(4) Viscosity (rotational viscosity; γ1; measured at 25° C.; mPa·s):Measurement was carried out according to a method described in M. Imaiet al., Molecular Crystals and Liquid Crystals, Vol. 259, p. 37 (1995).A sample was put in a VA device in which a distance (cell gap) betweentwo glass substrates was 20 micrometers. Voltage was applied stepwise tothe device in the range of 39 V to 50 V at an increment of 1 V. After aperiod of 0.2 second with no voltage application, voltage was repeatedlyapplied under conditions of only one rectangular wave (rectangularpulse; 0.2 second) and no voltage application (2 seconds). A peakcurrent and a peak time of transient current generated by the appliedvoltage were measured. A value of rotational viscosity was obtained fromthe measured values and calculation equation (8) described on page 40 ofthe paper presented by M. Imai et al. Dielectric anisotropy required forthe calculation was measured according to section 6.

(5) Optical anisotropy (refractive index anisotropy; Δn; measured at 25°C.): Measurement was carried out by an Abbe refractometer with apolarizing plate mounted on an ocular, using light at a wavelength of589 nanometers. A surface of a main prism was rubbed in one direction,and then a sample was added dropwise onto the main prism. A refractiveindex (n∥) was measured when a direction of polarized light was parallelto a direction of rubbing. A refractive index (n⊥) was measured when thedirection of polarized light was perpendicular to the direction ofrubbing. A value of optical anisotropy was calculated from an equation:

Δn=n∥−n⊥.

(6) Dielectric anisotropy (Δ∈; measured at 25° C.): A value ofdielectric anisotropy was calculated from an equation: Δ∈=∈∥−∈⊥. Adielectric constant (∈∥ and ∈⊥) was measured as described below.

(1) Measurement of dielectric constant (∈∥): An ethanol (20 mL) solutionof octadecyltriethoxysilane (0.16 mL) was applied to a well-cleanedglass substrate. After rotating the glass substrate with a spinner, theglass substrate was heated at 150° C. for 1 hour. A sample was put in aVA device in which a distance (cell gap) between two glass substrateswas 4 micrometers, and the device was sealed with an ultraviolet-curableadhesive. Sine waves (0.5 V, 1 kHz) were applied to the device, andafter 2 seconds, a dielectric constant (∈∥) of liquid crystal moleculesin a major axis direction was measured.

(2) Measurement of dielectric constant (∈⊥): A polyimide solution wasapplied to a well-cleaned glass substrate. After calcining the glasssubstrate, rubbing treatment was applied to the alignment film obtained.A sample was put in a TN device in which a distance (cell gap) betweentwo glass substrates was 9 micrometers and a twist angle was 80 degrees.Sine waves (0.5 V, 1 kHz) were applied to the device, and after 2seconds, a dielectric constant (∈⊥) of liquid crystal molecules in aminor axis direction was measured.

(7) Threshold voltage (Vth; measured at 25° C.; V): For measurement, anLCD-5100 luminance meter made by Otsuka Electronics Co., Ltd. was used.A light source was a halogen lamp. A sample was put in a normally blackmode VA device in which a distance (cell gap) between two glasssubstrates was 4 micrometers and a rubbing direction was anti-parallel,and the device was sealed with an ultraviolet-curable adhesive. Avoltage (60 Hz, rectangular waves) to be applied to the device wasstepwise increased from 0 V to 20 V at an increment of 0.02 V. On theoccasion, the device was irradiated with light from a directionperpendicular to the device, and an amount of light transmitted throughthe device was measured. A voltage-transmittance curve was prepared, inwhich the maximum amount of light corresponds to 100% transmittance andthe minimum amount of light corresponds to 0% transmittance. A thresholdvoltage is expressed in terms of voltage at 10% transmittance.

(8) Voltage holding ratio (VHR-1; measured at 25° C.; %): A TN deviceused for measurement had a polyimide alignment film, and a distance(cell gap) between two glass substrates was 5 micrometers. A sample wasput in the device, and then the device was sealed with anultraviolet-curable adhesive. A pulse voltage (60 microseconds at 5 V)was applied to the TN device and the device was charged. A decayingvoltage was measured for 16.7 milliseconds with a high-speed voltmeter,and area A between a voltage curve and a horizontal axis in a unit cyclewas determined. Area B is an area without decay. A voltage holding ratiois expressed in terms of a percentage of area A to area B.

(9) Voltage holding ratio (VHR-2; measured at 80° C.; %): A voltageholding ratio was measured according to procedures identical with theprocedures described above except that measurement was carried out at80° C. in place of 25° C. The thus obtained value was expressed in termsof VHR-2.

(10) Voltage holding ratio (VHR-3; measured at 25° C.; %): Stability toultraviolet light was evaluated by measuring a voltage holding ratioafter a device was irradiated with ultraviolet light. A TN device usedfor measurement had a polyimide alignment film, and a cell gap was 5micrometers. A sample was injected into the device, and the device wasirradiated with light for 20 minutes. A light source was an ultrahigh-pressure mercury lamp USH-500D (made by Ushio, Inc.), and adistance between the device and the light source was 20 centimeters. Inmeasurement of VHR-3, a decaying voltage was measured for 16.7milliseconds. A composition having large VHR-3 has large stability toultraviolet light. A value of VHR-3 is preferably 90% or more, andfurther preferably 95% or more.

(11) Voltage holding ratio (VHR-4; measured at 25° C.; %): Stability toheat was evaluated by measuring a voltage holding ratio after a TNdevice into which a sample was injected was heated in aconstant-temperature bath at 80° C. for 500 hours. In measurement ofVHR-4, a decaying voltage was measured for 16.7 milliseconds. Acomposition having large VHR-4 has large stability to heat.

(12) Response time (T; measured at 25° C.; ms): For measurement, anLCD-5100 luminance meter made by Otsuka Electronics Co., Ltd. was used.A light source was a halogen lamp. A low-pass filter was set to 5 kHz. Asample was put in a normally black mode VA device in which a distance(cell gap) between two glass substrates was 4 micrometers and a rubbingdirection was anti-parallel. The device was sealed with anultraviolet-curable adhesive. A voltage (rectangular waves; 60 Hz, 10 V,0.5 second) was applied to the device. On the occasion, the device wasirradiated with light from a direction perpendicular to the device, andan amount of light transmitted through the device was measured. Themaximum amount of light corresponds to 100% transmittance, and theminimum amount of light corresponds to 0% transmittance. A response timewas expressed in terms of time required for a change from 90%transmittance to 10% transmittance (fall time; millisecond).

(13) Specific resistance (ρ; measured at 25° C.; 0 cm): Into a vesselequipped with electrodes, 1.0 milliliter of sample was injected. Adirect current voltage (10 V) was applied to the vessel, and a directcurrent after 10 seconds was measured. Specific resistance wascalculated from the following equation: (specificresistance)={(voltage)×(electric capacity of a vessel)}/{(directcurrent)×(dielectric constant of vacuum)}.

The compounds in Examples were represented using symbols according todefinitions in Table 3 described below. In Table 3, the configuration of1,4-cyclohexylene is trans. A parenthesized number next to a symbolizedcompound corresponds to the number of the compound. A symbol (-) meansany other liquid crystal compound. A proportion (percentage) of theliquid crystal compound is expressed in terms of weight percent (% byweight) based on the weight of the liquid crystal composition. Values ofthe characteristics of the composition were summarized in a last part.

TABLE 3 Method for Description of Compounds using Symbols R—(A₁)—Z₁— . .. —Z_(n)—(A_(n))—R′ 1) Left-terminal Group R— Symbol FC_(n)H_(2n)— Fn—C_(n)H_(2n+1)— n— C_(n)H_(2n+1)O— nO— C_(m)H_(2m+1)OC_(n)H_(2n)— mOn—CH₂═CH— V— C_(n)H_(2n+1)—CH═CH— nV— CH₂═CH—C_(n)H_(2n)— Vn—C_(m)H_(2m+1)—CH═CH—C_(n)H_(2n)— mVn— CF₂═CH— VFF— CF₂═CH—C_(n)H_(2n)—VFFn— C_(m)H_(2m+1)CF₂C_(n)H_(2n)— m(CF2)n— CH₂═CHCOO— AC—CH₂═C(CH₃)COO— MAC— 2) Right-terminal Group —R′ Symbol —C_(n)H_(2n+1) —n—OC_(n)H_(2n+1) —On —CH═CH₂ —V —CH═CH—C_(n)H_(2n+1) —Vn—C_(n)H_(2n)—CH═CH₂ —nV —C_(m)H_(2m)—CH═CH—C_(n)H_(2n+1) —mVn —CH═CF₂—VFF —OCOCH═CH₂ —AC —OCOC(CH₃)═CH₂ —MAC 3) Bonding Group —Z_(n)— Symbol—C_(n)H_(2n)— n —COO— E —CH=CH— V —CH=CHO— VO —OCH=CH— OV —CH₂O— 1O—OCH₂— O1 4) Right Structure —A_(n)— Symbol

H

B

B(F)

B(2F)

B(2F,5F)

B(2F,3F)

B(2F,3Cl)

dh

Dh

ch

Cro(7F,8F) 5) Examples of Description Example 1 V—HHB(2F,3F)—O2

Example 2 5—chB(2F,3F)—O2

Example 3 3—HBB—1

Example 4 AC—BB—AC

Comparative Example 1

Example 3.5 was selected from the compositions disclosed in JP2010-503733 A. The basis thereof is that the composition containscompound (1-1), compound (1-6), compound (1-10), compound (2-1),compound (2-2) and compound (5-9). Components and characteristics of thecomposition were as described below.

3-chB(2F,3F)-O2 (2-1) 17% V-HB(2F,3F)-O2 (1-1)  4% 3-HchB(2F,3F)-O2(2-2) 12% V-HHB(2F,3F)-O2 (1-6)  5% V-HBB(2F,3F)-O2 (1-10)  7%V-HBB(2F,3F)-O4 (1-10)  6% 3-HH-V1 (—) 12% 5-HH-V (—) 20% 2-BB(2F,3F)B-4(5-9)  9% 2-BB(2F,3F)B-3 (5-9)  8%

NI=81.0° C.; Δn=0.1271; Δ∈=−3.8; γ1=131 mPa·s.

Example 1

V-HB(2F,3F)-O2 (1-1) 10% V-HHB(2F,3F)-O2 (1-6) 10% V2-HHB(2F,3F)-O2(1-6) 10% V-HBB(2F,3F)-O2 (1-10) 10% 3-chB(2F,3F)-O2 (2-1) 10%3-HchB(2F,3F)-O2 (2-2) 10% 2-HH-3 (3) 24% 1-BB-3 (4-2)  8%3-HHB(2F,3F)-O2 (5-6)  5% 3-HBB(2F,3F)-O2 (5-10)  3%

NI=76.8° C.; Tc<−20° C.; Δn=0.105; Δ∈=−4.0; Vth=1.96 V; γ1=106.7 mPa·s.

Example 2

V-H1OB(2F,3F)-O4 (1-3)  8% V2-BB(2F,3F)-O2 (1-4) 10% V-HH2B(2F,3F)-O2(1-7)  8% V2-BB(2F,3F)B-1 (1-9) 10% V-chB(2F,3F)-O2 (2-1)  5%3-HchB(2F,3F)-O2 (2-2) 10% 3-chBB(2F,3F)-O2 (2-3)  5% 2-HH-3 (3) 25%3-HB-O2 (4-1)  6% 3-HHEH-3 (4-3)  5% 3-HB(2F,3F)-O2 (5-1)  3%3-HHB(2F,3F)-O2 (5-6)  5%

NI=70.4° C.; Tc<−20° C.; Δn=0.110; Δ∈=−3.7; Vth=1.99 V; γ1=101.5 mPa·s.

Example 3

V-HB(2F,3F)-O2 (1-1) 12% V-HHB(2F,3F)-O2 (1-6)  9% V-HH1OB(2F,3F)-O2(1-8)  7% 1V-HH1OB(2F,3F)-O2 (1-8)  6% V-HDhB(2F,3F)-O2 (1-16)  3%3-chB(2F,3F)-O2 (2-1)  6% 3-HchB(2F,3F)-O2 (2-2)  4% 5-HchB(2F,3F)-O2(2-2) 10% V-HchB(2F,3F)-O2 (2-2)  3% 3-chB(2F)B(2F,3F)-O2 (2-4)  3%2-HH-3 (3) 25% 5-HB-O2 (4-1)  4% V2-HHB-1 (4-4)  6%5-B(2F,3F)B(2F,3F)-O2 (5-5)  2%

NI=80.1° C.; Tc<−20° C.; Δn=0.093; Δ∈=−4.3; Vth=1.93 V; γ1=113.6 mPa·s.

Example 4

V-HB(2F,3F)-O2 (1-1)  6% V-HB(2F,3F)-O4 (1-1)  8% 1V2-BB(2F,3F)-O2 (1-4) 5% V-HHB(2F,3F)-O2 (1-6)  8% V2-HHB(2F,3F)-O2 (1-6) 10% V-HBB(2F,3F)-O2(1-10)  5% 3-chB(2F,3F)-O2 (2-1)  7% V-chB(2F,3F)-O2 (2-1)  6%3-HchB(2F,3F)-O2 (2-2)  8% V2-HchB(2F,3F)-O2 (2-2)  3% 2-HH-3 (3) 23%2-BB(F)B-2V (4-6)  5% 3-HHEBH-3 (4-9)  3% 3-H1OB(2F,3F)-O2 (5-3)  3%

NI=71.1° C.; Tc<−20° C.; Δn=0.101; Δ∈=−4.1; Vth=1.93 V; γ1=111.3 mPa·s.

Example 5

V-HB(2F,3F)-O2 (1-1) 10% V2H1OB(2F,3F)-O4 (1-3)  5% 1V2-BB(2F,3F)-O2(1-4)  8% V-HHB(2F,3F)-O2 (1-6)  8% V-HHB(2F,3F)-O4 (1-6)  3%V-HBB(2F,3F)-O2 (1-10)  3% V-HHB(2F,3Cl)-O2 (1-12)  3% 2-HchB(2F,3F)-O2(2-2)  5% V-HchB(2F,3F)-O2 (2-2)  5% 1V2-HchB(2F,3F)-O2 (2-2)  7% 2-HH-3(3) 26% V2-BB-1 (4-2)  5% 5-B(F)BB-2 (4-7)  3% 3-HB(F)HH-2 (4-8)  3%3-BB(2F,3F)-O2 (5-4)  3% 3-HH2B(2F,3F)-O2 (5-7)  3%

NI=73.8° C.; Tc<−20° C.; Δn=0.105; Δ∈=−3.6; Vth=2.00 V; γ1=104.4 mPa·s.

Example 6

V-H1OB(2F,3F)-O4 (1-3)  3% V2H1OB(2F,3F)-O4 (1-3)  5% 1V2-BB(2F,3F)-O2(1-4)  6% V-HHB(2F,3F)-O1 (1-6)  4% V-HH2B(2F,3F)-O1 (1-7)  5%V-HH2B(2F,3F)-O2 (1-7)  5% V-HH2B(2F,3F)-O4 (1-7)  5% V-HBB(2F,3F)-O2(1-10)  7% 3-chB(2F,3F)-O2 (2-1)  8% 1V-HchB(2F,3F)-O2 (2-2)  5%2V1-HchB(2F,3F)-O2 (2-2)  3% 2-HH-3 (3) 24% VFF-HHB-1 (4-4)  4%VFF2-HHB-1 (4-4)  3% 2-BB(2F,3F)B-3 (5-9)  3% 3-HEB(2F,3F)B(2F,3F)-O2(5-11)  3% 2-HH-5 (—)  3% 3-HH-4 (—)  4%

NI=76.2° C.; Tc<−20° C.; Δn=0.100; Δ∈=−3.4; Vth=2.01 V; γ1=108.4 mPa·s.

Example 7

V-HB(2F,3F)-O2 (1-1) 10% V-HHB(2F,3F)-O2 (1-6) 12% V-HH1OB(2F,3F)-O2(1-8)  3% V-HBB(2F,3F)-O4 (1-10)  3% V-HDhB(2F,3F)-O4 (1-16)  3%V2-dhBB(2F,3F)-O2 (1-17)  3% V-chB(2F,3F)-O2 (2-1)  8% V-HchB(2F,3F)-O2(2-2)  8% V1-HchB(2F,3F)-O2 (2-2)  5% 2-HH-3 (3) 20% V2-BB-1 (4-2)  3%3-HHB-O1 (4-4)  5% 3-HHB-1 (4-4)  5% 3-HB(2F,3F)-O2 (5-1)  5%2-HBB(2F,3F)-O2 (5-10)  3% 3-HH-O1 (—)  4%

NI=72.6° C.; Tc<−20° C.; Δn=0.094; Δ∈=−3.9; Vth=1.96 V; γ1=114.7 mPa·s.

Example 8

V-HB(2F,3F)-O2 (1-1) 10% V-HHB(2F,3F)-O2 (1-6) 10% V2-HHB(2F,3F)-O2(1-6) 10% V-HBB(2F,3F)-O2 (1-10) 10% 3-chB(2F,3F)-O2 (2-1) 10%3-HchB(2F,3F)-O2 (2-2) 10% 5-HchB(2F,3F)-O2 (2-2)  8% 2-HH-3 (3) 24%1V2-HH-2V1 (—)  8%

NI=87.3° C.; Tc<−20° C.; Δn=0.099; Δ∈=−4.0; Vth=1.98 V; γ1=99.8 mPa·s.

Example 9

V-HB(2F,3F)-O2 (1-1) 10% V2-BB(2F,3F)-O2 (1-4)  4% 1V2-BB(2F,3F)-O2(1-4)  4% V2-HHB(2F,3F)-O2 (1-6) 10% V-HH1OB(2F,3F)-O2V (1-8)  3%V-HDhB(2F,3F)-O1 (1-16)  2% 1V-dhBB(2F,3F)-O2 (1-17)  3%3-HchB(2F,3F)-O2 (2-2)  6% V-HchB(2F,3F)-O2 (2-2) 10% 1V-HchB(2F,3F)-O2(2-2)  3% 5-chB(2F,3F)B(2F,3F)-O2 (2-5)  3% 2-HH-3 (3) 25% 1V2-BB-1(4-2)  9% 5-HB(F)BH-3 (4-11)  3% 3-HBB(2F,3Cl)-O2 (5-13)  2% 1O1-HBBH-5(—)  3%

NI=85.7° C.; Tc<−20° C.; Δn=0.113; Δ∈=−3.1; Vth=2.05 V; γ1=108.4 mPa·s.

Example 10

V-HHB(2F,3F)-O2 (1-6) 10% V-HHB(2F,3F)-O4 (1-6)  5% V2-HHB(2F,3F)-O2(1-6) 10% V-HBB(2F,3F)-O2 (1-10) 10% 3-chB(2F,3F)-O2 (2-1) 10%3-HchB(2F,3F)-O2 (2-2) 10% 2-HH-3 (3) 24% 5-HB-O2 (4-1)  5% V2-BB-1(4-2)  6% 3-HBB-2 (4-5)  5% 3-H1OCro(7F,8F)-5 (5-14)  2%3-HH1OCro(7F,8F)-5 (5-15)  3%

NI=88.0° C.; Tc<−20° C.; Δn=0.106; Δ∈=−3.5; Vth=2.03 V; γ1=111.3 mPa·s.

Example 11

V-HB(2F,3F)-O2 (1-1) 10% V-HHB(2F,3F)-O2 (1-6) 10% V2-HHB(2F,3F)-O2(1-6) 10% V-HBB(2F,3F)-O2 (1-10)  6% 2V-dhBB(2F,3F)-O2 (1-17)  3%V-chB(2F,3F)-O2 (2-1) 10% 5-HchB(2F,3F)-O2 (2-2)  8% 3-HchB(2F,3F)-O3(2-2)  3% 4O-chBB(2F,3F)-O2 (2-3)  2% 2-HH-3 (3) 22% 7-HB-1 (4-1)  8%2-BB(F)B-3 (4-6)  3% 3-H2B(2F,3F)-O2 (5-2)  3% 3-HDhB(2F,3F)-O2 (5-16) 2%

NI=70.7° C.; Tc<−20° C.; Δn=0.099; Δ∈=−3.9; Vth=1.97 V; γ1=112.4 mPa·s.

Example 12

V-HB(2F,3F)-O2 (1-1) 10% V-HHB(2F,3F)-O2 (1-6) 10% V2-HHB(2F,3F)-O2(1-6) 10% V-HBB(2F,3F)-O2 (1-10) 10% 3-chB(2F,3F)-O2 (2-1) 10%3-HchB(2F,3F)-O2 (2-2) 10% 2-HH-3 (3) 24% 1-BB-5 (4-2)  8%3-HHB(2F,3F)-O2 (5-6)  5% 3-dhBB(2F,3F)-O2 (5-17)  3%

NI=77.1° C.; Tc<−20° C.; Δn=0.105; Δ∈=−4.0; Vth=1.96 V; γ1=108.4 mPa·s.

Example 13

V-HB(2F,3F)-O2 (1-1) 10% V-HHB(2F,3F)-O2 (1-6) 10% V-HH1OB(2F,3F)-O2(1-8)  5% V-HBB(2F,3F)-O2 (1-10)  7% V-HDhB(2F,3F)-O2 (1-16)  3%V2-dhBB(2F,3F)-O2 (1-17)  3% 3-chB(2F,3F)-O2 (2-1)  8% 3-HchB(2F,3F)-O3(2-2)  8% 3V-HchB(2F,3F)-O2 (2-2)  5% 2-HH-3 (3) 20% V2-BB-1 (4-2)  5%3-HHB-1 (4-4)  5% 3-HB(2F,3F)-O2 (5-1)  5% 3-HBB(2F,3F)-O2 (5-10)  3%5-HH-O1 (—)  3%

NI=75.4° C.; Tc<−20° C.; Δn=0.103; Ac=−4.2; Vth=1.79 V; γ1=104.3 mPa·s.

Example 14

V-HB(2F,3F)-O2 (1-1) 10% 3V-B(2F,3F)B(2F,3F)-O2 (1-5)  2%V2-HHB(2F,3F)-O2 (1-6) 10% V-HH1OB(2F,3F)-O2 (1-8)  3%1V-HH1OB(2F,3F)-O2 (1-8)  3% V2-HHB(2F,3Cl)-O2 (1-12)  3%3-HchB(2F,3F)-O2 (2-2)  4% 5-HchB(2F,3F)-O2 (2-2)  6% V-HchB(2F,3F)-O2(2-2) 10% 3-chB(2F)B(2F,3F)-O2 (2-4)  3% 4O-chB(2F,3F)B(2F,3F)-O2 (2-5) 2% 2-HH-3 (3) 25% 1-BB-3 (4-2)  7% V-HHB-1 (4-4)  3% V-HBB-3 (4-5)  3%3-H2B(2F,3F)-O2 (5-2)  3% 5-H23(2F,3F)-O2 (5-2)  3%

NI=78.3° C.; Tc<−20° C.; Δn=0.102; Δ∈=−3.7; Vth=2.00 V; γ1=105.0 mPa·s.

Example 15

V-H1OB(2F,3F)-O4 (1-3)  6% V2-BB(2F,3F)-O2 (1-4) 10% V-HH2B(2F,3F)-O2(1-7)  8% V2-BB(2F,3F)B-1 (1-9) 10% V-dhBB(2F,3F)-O2 (1-17)  3%V-chB(2F,3F)-O2 (2-1)  5% 3-HchB(2F,3F)-O2 (2-2) 10% 3-chBB(2F,3F)-O2(2-3)  5% 2-HH-3 (3) 23% 3-HB-O2 (4-1)  6% 3-HHEH-3 (4-3)  5% 5-HBBH-3(4-10)  3% 3-HB(2F,3F)-O2 (5-1)  3% 3-HHB(2F,3F)-O2 (5-6)  3%

NI=78.6° C.; Tc<−20° C.; Δn=0.117; Δ∈=−3.6; Vth=2.02 V; γ1=113.6 mPa·s.

Example 16

V-HB(2F,3F)-O2 (1-1) 10% V2H1OB(2F,3F)-O4 (1-3)  4% 1V2-BB(2F,3F)-O2(1-4) 12% V-HHB(2F,3F)-O2 (1-6)  8% V-HBB(2F,3F)-O2 (1-10)  3%V-HHB(2F,3Cl)-O2 (1-12)  3% 1V2-dhBB(2F,3F)-O2 (1-17)  3%3-HchB(2F,3F)-O2 (2-2)  5% V-HchB(2F,3F)-O2 (2-2)  7% V2-HchB(2F,3F)-O2(2-2)  5% 2-HH-3 (3) 26% V2-BB-1 (4-2)  6% 5-HBB(F)B-2 (4-12)  2%5-BB(2F,3F)-O2 (5-4)  3% 3-HHB(2F,3Cl)-O2 (5-12)  3%

NI=70.3° C.; Tc<−20° C.; Δn=0.105; Δ∈=−3.8; Vth=1.97 V; γ1=109.6 mPa·s.

Example 17

V-HB(2F,3F)-O2 (1-1)  8% V-HB(2F,3F)-O4 (1-1)  6% 1V2-BB(2F,3F)-O2 (1-4) 5% V-HHB(2F,3F)-O2 (1-6)  7% V2-HHB(2F,3F)-O2 (1-6) 10% V-HBB(2F,3F)-O2(1-10)  5% 3-chB(2F,3F)-O2 (2-1)  7% V-chB(2F,3F)-O2 (2-1)  6%3-HchB(2F,3F)-O2 (2-2)  8% V2-HchB(2F,3F)-O2 (2-2)  3% 2-HH-3 (3) 23%3-HHB-3 (4-4)  3% 1-BB(F)B-2V (4-6)  3% 3-HHEBH-5 (4-9)  3%2-HH1OB(2F,3F)-O2 (5-8)  3%

NI=76.3° C.; Tc<−20° C.; Δn=0.100; Δ∈=−4.1; Vth=1.95 V; γ1=111.3 mPa·s.

Example 18

V-HB(2F,3F)-O2 (1-1)  7% V-HB(2F,3F)-O4 (1-1)  5% V2-HHB(2F,3F)-O2 (1-6)10% V-HH2B(2F,3F)-O3 (1-7) 10% V-HBB(2F,3F)-O2 (1-10)  5%1V-HHB(2F,3Cl)-O2 (1-12)  3% 3-chB(2F,3F)-O2 (2-1) 11% 3-HchB(2F,3F)-O2(2-2)  7% 3V-HchB(2F,3F)-O2 (2-2)  3% V3-HchB(2F,3F)-O2 (2-2)  3% 2-HH-3(3) 24% V-HBB-2 (4-5)  9% 2-HHB(2F,3F)-O2 (5-6)  3%

NI=81.1° C.; Tc<−20° C.; Δn=0.098; Δ∈=−3.5; Vth=2.02 V; γ1=110.1 mPa·s.

The compositions in Example 1 to Example 18 had smaller viscosity incomparison with the composition in Comparative Example 1. Accordingly,the liquid crystal composition of the invention is concluded to havesuperb characteristics.

INDUSTRIAL APPLICABILITY

A liquid crystal composition of the invention satisfies at least one ofcharacteristics such as high maximum temperature, low minimumtemperature, small viscosity, suitable optical anisotropy, largenegative dielectric anisotropy, large specific resistance, highstability to ultraviolet light and high stability to heat, or has asuitable balance regarding at least two of the characteristics. A liquidcrystal display device including the composition has characteristicssuch as a short response time, a large voltage holding ratio, lowthreshold voltage, a large contrast ratio and a long service life, andthus can be used in a liquid crystal projector, a liquid crystaltelevision and so forth.

1. A liquid crystal composition that has negative dielectric anisotropy,and contains at least one compound selected from the group of compoundsrepresented by formula (1) as a first component, at least one compoundselected from the group of compounds represented by formula (2) as asecond component and a compound represented by formula (3) as a thirdcomponent:

wherein, in formula (1) and formula (2), R¹ is alkenyl having 2 to 12carbons, R², R³ and R⁴ are independently alkyl having 1 to 12 carbons,alkoxy having 1 to 12 carbons, alkenyl having 2 to 12 carbons,alkenyloxy having 2 to 12 carbons, or alkyl having 1 to 12 carbons inwhich at least one hydrogen is replaced by fluorine or chlorine; ring Aand ring C are independently 1,4-cyclohexylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine; ring D and ringF are independently 1,4-cyclohexylene, 1,4-cyclohexenylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine, in which atleast one of ring D and ring F is 1,4-cyclohexenylene; ring B is2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl; ring E is 2,3-difluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl; Z¹, Z², Z³ and Z⁴ are independently asingle bond, ethylene, carbonyloxy or methyleneoxy; a is 1, 2 or 3; b is0 or 1; a sum of a and b is 3 or less; c is 1, 2 or 3; d is 0 or 1; anda sum of c and d is 3 or less.
 2. The liquid crystal compositionaccording to claim 1, containing at least one compound selected from thegroup of compounds represented by formula (1-1) to formula (1-17) as thefirst component:

wherein, in formula (1-1) to formula (1-17), R¹ is alkenyl having 2 to12 carbons, R² is alkyl having 1 to 12 carbons, alkoxy having 1 to 12carbons, alkenyl having 2 to 12 carbons, alkenyloxy having 2 to 12carbons, or alkyl having 1 to 12 carbons in which at least one hydrogenis replaced by fluorine or chlorine.
 3. The liquid crystal compositionaccording to claim 1, containing at least one compound selected from thegroup of compounds represented by formula (2-1) to formula (2-5) as thesecond component:

wherein, in formula (2-1) to formula (2-5), R³ and R⁴ are independentlyalkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenylhaving 2 to 12 carbons, alkenyloxy having 2 to 12 carbons, or alkylhaving 1 to 12 carbons in which at least one hydrogen is replaced byfluorine or chlorine.
 4. The liquid crystal composition according toclaim 1, wherein a proportion of the first component is in the range of5% by weight to 60% by weight, a proportion of the second component isin the range of 5% by weight to 50% by weight, and a proportion of thethird component is in the range of 5% by weight to 35% by weight, basedon the weight of the liquid crystal composition.
 5. The liquid crystalcomposition according to claim 1, containing at least one compoundselected from the group of compounds represented by formula (4) as afourth component:

wherein, in formula (4), R⁵ and R⁶ are independently alkyl having 1 to12 carbons, alkoxy having 1 to 12 carbons, alkenyl having 2 to 12carbons, alkyl having 1 to 12 carbons in which at least one hydrogen isreplaced by fluorine or chlorine, or alkenyl having 2 to 12 carbons inwhich at least one hydrogen is replaced by fluorine or chlorine; ring Gand ring I are independently 1,4-cyclohexylene, 1,4-phenylene,2-fluoro-1,4-phenylene or 2,5-difluoro-1,4-phenylene; Z⁵ is a singlebond, ethylene or carbonyloxy; e is 1, 2 or 3; and when e is 1, ring Iis 1,4-phenylene.
 6. The liquid crystal composition according to claim5, containing at least one compound selected from the group of compoundsrepresented by formula (4-1) to formula (4-12) as the fourth component:

wherein, in formula (4-1) to formula (4-12), R⁵ and R⁶ are independentlyalkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, alkenylhaving 2 to 12 carbons, alkyl having 1 to 12 carbons in which at leastone hydrogen is replaced by fluorine or chlorine, or alkenyl having 2 to12 carbons in which at least one hydrogen is replaced by fluorine orchlorine.
 7. The liquid crystal composition according to claim 5,wherein a proportion of the fourth component is in the range of 5% byweight to 40% by weight based on the weight of the liquid crystalcomposition.
 8. The liquid crystal composition according to claim 1,containing at least one compound selected from the group of compoundsrepresented by formula (5) as a fifth component:

wherein, in formula (5), R⁷ and R⁸ are independently alkyl having 1 to12 carbons, alkoxy having 1 to 12 carbons, or alkyl having 1 to 12carbons in which at least one hydrogen is replaced by fluorine orchlorine; ring N and ring P are independently 1,4-cyclohexylene,tetrahydropyran-2,5-diyl, 1,4-phenylene, or 1,4-phenylene in which atleast one hydrogen is replaced by fluorine or chlorine; ring Q is2,3-difluoro-1,4-phenylene, 2-chloro-3-fluoro-1,4-phenylene,2,3-difluoro-5-methyl-1,4-phenylene, 3,4,5-trifluoronaphthalene-2,6-diylor 7,8-difluorochroman-2,6-diyl; Z⁶ and Z⁷ are independently a singlebond, ethylene, carbonyloxy or methyleneoxy; p is 1, 2 or 3; q is 0 or1; and a sum of p and q is 3 or less.
 9. The liquid crystal compositionaccording to claim 8, containing at least one compound selected from thegroup of compounds represented by formula (5-1) to formula (5-17) as thefifth component:

wherein, in formula (5-1) to formula (5-17), R⁷ and R⁸ are independentlyalkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, or alkylhaving 1 to 12 carbons in which at least one hydrogen is replaced byfluorine or chlorine.
 10. The liquid crystal composition according toclaim 8, wherein a proportion of the fifth component is in the range of5% by weight to 50% by weight based on the weight of the liquid crystalcomposition.
 11. The liquid crystal composition according to claim 1,containing at least one polymerizable compound selected from the groupof compounds represented by formula (6) as an additive component:

wherein, in formula (6), ring K and ring M are independently cyclohexyl,cyclohexenyl, phenyl, 1-naphthyl, 2-naphthyl, tetrahydropyran-2-yl,1,3-dioxane-2-yl, pyrimidine-2-yl or pyridine-2-yl, and in the rings, atleast one hydrogen may be replaced by fluorine, chlorine, alkyl having 1to 12 carbons, alkoxy having 1 to 12 carbons, or alkyl having 1 to 12carbons in which at least one hydrogen is replaced by fluorine orchlorine; ring L is 1,4-cyclohexylene, 1,4-cyclohexenylene,1,4-phenylene, naphthalene-1,2-diyl, naphthalene-1,3-diyl,naphthalene-1,4-diyl, naphthalene-1,5-diyl, naphthalene-1,6-diyl,naphthalene-1,7-diyl, naphthalene-1,8-diyl, naphthalene-2,3-diyl,naphthalene-2,6-diyl, naphthalene-2,7-diyl, tetrahydropyran-2,5-diyl,1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl or pyridine-2,5-diyl, and inthe rings, at least one hydrogen may be replaced by fluorine, chlorine,alkyl having 1 to 12 carbons, alkoxy having 1 to 12 carbons, or alkylhaving 1 to 12 carbons in which at least one hydrogen is replaced byfluorine or chlorine; Z⁸ and Z⁹ are independently a single bond oralkylene having 1 to 10 carbons, and in the alkylene, at least one pieceof —CH₂— may be replaced by —O—, —CO—, —COO— or —OCO—, and at least onepiece of —CH₂—CH₂— may be replaced by —CH═CH—, —C(CH₃)═CH—, —CH═C(CH₃)—or —C(CH₃)═C(CH₃)—, and in the groups, at least one hydrogen may bereplaced by fluorine or chlorine; P¹, P² and P³ are independently apolymerizable group; Sp¹, Sp² and Sp³ are independently a single bond oralkylene having 1 to 10 carbons, and in the alkylene, at least one pieceof —CH₂— may be replaced by —O—, —COO—, —OCO— or —OCOO—, and at leastone piece of —CH₂—CH₂— may be replaced by —CH═CH— or —C≡C—, and in thegroups, at least one hydrogen may be replaced by fluorine or chlorine; gis 0, 1 or 2; h, j and k are independently 0, 1, 2, 3 or 4; and a sum ofh, j and k is 1 or more.
 12. The liquid crystal composition according toclaim 11, wherein, in formula (6), P¹, P² and P³ are independently apolymerizable group selected from the group of groups represented byformula (P-1) to formula (P-5):

wherein, in formula (P-1) to formula (P-5), M¹, M² and M³ areindependently hydrogen, fluorine, alkyl having 1 to 5 carbons, or alkylhaving 1 to 5 carbons in which at least one hydrogen is replaced byfluorine or chlorine.
 13. The liquid crystal composition according toclaim 11, containing at least one polymerizable compound selected fromthe group of compounds represented by formula (6-1) to formula (6-27) asthe additive component:

wherein, in formula (6-1) to formula (6-27), P⁴, P⁵ and P⁶ areindependently a polymerizable group selected from the group of groupsrepresented by formula (P-1) to formula (P-3);

wherein, in formula (P-1) to formula (P-3), M¹, M² and M³ areindependently hydrogen, fluorine, alkyl having 1 to 5 carbons, or alkylhaving 1 to 5 carbons in which at least one hydrogen is replaced byfluorine or chlorine; and in formula (6-1) to formula (6-27), Sp¹, Sp²and Sp³ are independently a single bond or alkylene having 1 to 10carbons, and in the alkylene, at least one piece of —CH₂— may bereplaced by —O—, —COO—, —OCO— or —OCOO—, and at least one piece of—CH₂—CH₂— may be replaced by —CH═CH— or —C≡C—, and in the groups, atleast one hydrogen may be replaced by fluorine or chlorine.
 14. Theliquid crystal composition according to claim 11, wherein a proportionof addition of the additive component is in the range of 0.03% by weightto 10% by weight based on the weight of the liquid crystal composition.15. A liquid crystal display device, including the liquid crystalcomposition according to claim
 1. 16. The liquid crystal display deviceaccording to claim 15, wherein an operating mode in the liquid crystaldisplay device includes an IPS mode, a VA mode, an FFS mode or an FPAmode, and a driving mode in the liquid crystal display device includesan active matrix mode.
 17. A polymer sustained alignment mode liquidcrystal display device, wherein the liquid crystal display deviceincludes the liquid crystal composition according to claim 11, or thepolymerizable compound in the liquid crystal composition is polymerized.18. (canceled)
 19. (canceled)